勢力圏|せいりょくけんseiryokuken

1. nounsphere of influence

• Synonym領分りょうぶんNeutralLeans personal: one's own turf or range of duties rather than a nation's reach, as in 「領分を侵す」.
• Synonym勢力範囲せいりょくはんいWrittenAlmost synonymous with 「勢力圏」 and freely interchangeable; unlike the headword, it sits comfortably in both speech and writing.
• Synonym影響圏えいきょうけんWrittenA written word for the range that power or influence can reach; very close to 「勢力圏」 in meaning.

Use 「勢力圏」, a written word, for areas where a country or organization wields political or economic control or influence, as in 「大国の勢力圏」. 「勢力範囲」 says much the same and also fits speech. For a person's own turf or duties, use 「領分」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. ある国くにや団体だんたいなどが政治的せいじてき・経済的けいざいてきに支配しはい・影響えいきょうを及およぼしている地域ちいき。